maint: Clean up BIST tests so they don't produce warnings. * data.cc (Fhorzcat): Temporarily disable "num-to-str" warning for BIST tests. * luinc.cc (__luinc__): Move BIST tests to luinc.m. * luinc.m: Add BIST tests for luinc. * regexp.cc (Fregexp): Temporarily disable "regexp-lookbehind-limit" for BIST tests. * sqrtm.cc (Fsqrtm): Temporarily disable "sqrtm:SingularMatrix" for BIST tests. * __eigs__.cc, __init_fltk__.cc, __init_gnuplot__.cc: Add 'assert (1)' BIST test to mark internal functions as tested. * ov-range.cc (Fallow_noninteger_range_as_index: Temporarily disable "deprecated-syntax" for BIST tests. * quadv.m: Temporarily disable "divide-by-zero" warning for BIST tests. * imfinfo.m: Temporarily disable "GraphicsMagic-Quantum-Depth" for BIST tests.

--- a/libinterp/dldfcn/__init_fltk__.cc	Fri Apr 01 12:57:49 2016 -0400
+++ b/libinterp/dldfcn/__init_fltk__.cc	Fri Apr 01 13:56:09 2016 -0700
@@ -1,6 +1,5 @@
 /*
 
-
 Copyright (C) 2007-2015 Shai Ayal
 Copyright (C) 2014-2015 Andreas Weber
 
@@ -2439,3 +2438,8 @@
   err_disabled_feature ("__init_fltk__", "OpenGL and FLTK");
 #endif
 }
+
+/*
+## No test needed for internal helper function.
+%!assert (1)
+*/